Super Paper Mario Hard Mode: Dimentio (1)
3Mod location: https://github.com/L5050/Flipside-Mod-Manager
Now this was this first boss of the mod that felt like I was getting my ass kicked throughout and I was on the verge of a failed first attempt going so far as my safety net life shroom getting used up in this fight and making my Ice Storm go to waste making me wish I didn't waste those other items on that Bowser fight.
Dimentio already has faster tempo as far as casting and even the movement after casting their magic being real fast making them a pain to jump on and grab with Thoreau (even their stun-lock after the grab isn't very long at all and ends very quickly). But on top of that, they take a lot less damage now and will hit so much harder if you come in contact with the real Dimentio's spells or get an improper hit on them.
But similar to the Mimi fight, a cheese strat I found out is once you get ahold of the real Dimentio with Thoreau, throwing them into a corner feels like you get a lot more wiggle room time to try and hit them before the very fast stun-lock ends and chip them down, and Peach's Parasol also helps a lot when trying to negate the casting attacks, but there is still a good chance that you will be in the open yourself to damage when trying to do everything else in this fight.